1. Field
The present invention relates to a rechargeable battery.
2. Description of the Related Art
Unlike a primary battery that is not rechargeable, a rechargeable battery can be discharged and recharged. A small-capacity rechargeable battery is used for small portable electronic devices such as mobile phones, notebook computers, camcorders, and the like, while a large-capacity rechargeable battery is used as a motor-driving power source for a hybrid vehicle, and the like.
Recently, a high-output rechargeable battery using a non-aqueous electrolyte of high energy density has been developed, and a plurality of high-output rechargeable batteries may be connected in series to constitute a large-capacity battery module to be used for driving a motor of a device, e.g., an electric automobile or the like, that requires much power.
Also, a single large-capacity high-output rechargeable battery generally includes a plurality of rechargeable batteries connected in series, and such rechargeable batteries may have a cylindrical shape, an angular (i.e., rectangular or quadrangular) shape, a pouch-like shape, or the like.
In a typical rechargeable battery, a positive electrode and a negative electrode are generally charged by coating an active material on a base. A separator is located between the positive and negative electrodes, and are then wound and compressed to fit an angular case and housed therein.
Sometimes, however, the electrode assembly in the interior of the case expands and contracts when the rechargeable battery is charged and discharged, resulting in the active material coated on the base becoming detached or released, or degraded. In addition, when an impact from outside of the rechargeable battery is applied to the electrode assembly, the shape of the electrode assembly may be deformed, making the rechargeable battery defective.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.